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    <title>Document</title>
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    <script>
        /* 
             九九乘法表:双重for循环

             *
             **
             ***
             ****

             i    num(j 的最大值)
             0     1
             1     2
             2     3
             
             i + 1 = num
        */
        for (let i = 1; i < 10; i++) {

let star = '';
for (let k = 1; k < i + 1; k++) {
    star = star + (i + "*" + k + "=" + i * k) + " ";
}
console.log(star);
}
 
console.log("案例--------------------------")



for (let i = 1; i < 10; i++){
    let star = ' ';
    for (let k =1; k < i + 1; k++){
        star = star + (i + '*' + k + '=' + i * k + ' ')
    }
console.log(star);
}
console.log("案例--------------------------")




    </script>
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